1. Field of the Invention
The present invention relates to a disk drive, and more particularly, to a clamper for securing a data storage disk to a turntable.
2. Description of the Related Art
A disk drive is an apparatus to read data from and/or write data to a disk-type optical medium (hereinafter referred to as an optical disk), such as compact disk (CD), digital video disk (DVD), or the like, by irradiating a light onto the optical disk.
FIG. 1A is a partial cross-sectional view illustrating one example of a conventional clamper, and FIG. 1B is a partial cross-sectional view illustrating a disk clamped to a turntable by the damper shown in FIG. 1A.
Referring to FIG. 1A, a damper 20 is supported on a support frame 11 protruded downwardly along an edge of an opening formed at an upper case 10. A cover 13 is placed on the opening of the upper case 10 to close the opening. The damper 20 is arranged in such a manner that it can move up and down within a space 30 defined by the opening.
The cover 13 is provided under a bottom thereof with a damper 23 for preventing the clamper 20 from being raised and colliding against the cover 13 and absorbing a shock. The damper 23 is spaced apart from the damper 20 at a given distance.
Referring to FIG. 1B, when a turntable 14 with a disk D seated thereon approaches the clamper 20, a magnet 15 provided inside of the turntable 14 is magnetically adhered to a bracket 21 provided inside of the clamper 20, such that the disk D is secured between the clamper 20 and the turntable 14. The turntable 14 is turned by a spindle motor 16.
While the clamper 20 is moved upward by the turntable 14, the clamper 20 is spaced apart from the support frame 11 at a desired distance. Consequently, the clamper 20 is closer to the damper 23 relative to the spacing shown in FIG. 1A.
It is very difficult to set and maintain a spacing between the clamper 20 and the damper 23. Specifically, according to tests, when turntable 14 receives a shock, the clamper 20 does not stably operate, unless spaced apart from the damper 23. These tests included an operating shock test and a non-operating shock test. Consequently, it was determined that the damper 23 does not effectively prevent the clamper 20 from being spaced apart from the turntable 14 when an external shock is applied to the turntable 14, which can cause the disk to release from the turntable.
FIG. 2A is a partial cross-sectional view illustrating another example of a conventional clamper, and FIG. 2B is a partial cross-sectional view illustrating a disk clamped to a turntable by the clamper shown in FIG. 2A.
Referring to FIGS. 2A and 2B, a clamper 40 is provided on an upper surface thereof with a damper 43 and below there is a magnet 41. Since the cover 13 provided on the upper case 10 is made of a soft material, the cover 13 restricts the distance by which the clamper 40 moves upward in cooperation with the damper 43.
The shock tests (operating and non-operating) revealed that the clamper 40 and damper 43 were spaced apart from each other in a similar manner as discussed with respect to the structure of FIGS. 1A and 1B.
Furthermore, since the cover 13 is made of the soft material, the cover is easily affected by a force exerted from the outside, which prevents a smooth operation of the clamper 40.